1. Field of the Invention
The present invention relates to a list display apparatus for displaying a list including a plurality of items, a list display control method, and an information storage medium storing a program for realizing the method.
2. Description of the Related Art
There is a case where many items, such as messages posted by a plurality of users and a plurality of music data, are to be displayed on a screen. In this case, the following user interface technology is often adopted. A plurality of items sorted by various criteria are arranged in a list one-dimensionally. Some items included in a range to be displayed are displayed on the screen, and the range to be displayed is moved in accordance with a user's scroll operation. For instance, if the screen is a touch screen, the user can scroll items displayed on the screen by sliding a user's finger on the screen so as to instruct the scroll operation. According to this user interface, even if all items cannot be displayed on the screen at one time, the user can obtain a display of arbitrary items in the list on the screen by the scroll operation.
However, according to the above-mentioned user interface technology, when the scroll operation is performed to largely move the range to be displayed in the list, a processing load is increased because it is necessary to render all the items passing through the range to be displayed while the scroll operation is performed. Then, if rendering of each item takes long time, a speed of the scroll operation may be restricted because the rendering process is delayed. On the other hand, if there is no rendering of items in the range to be displayed while the scroll operation is performed, the user cannot grasp what extent the range to be displayed is moving by the scroll operation from the screen display. As a result, it becomes difficult to obtain a display of desired items on the screen by the scroll operation.